![Attempting to Join Starling fails with the error message "An unexpected error has occurred. You may need to refresh your page (press F5)." (4338807) Attempting to Join Starling fails with the error message "An unexpected error has occurred. You may need to refresh your page (press F5)." (4338807)](https://prod-support-images-cfm.s3.amazonaws.com/KB_1-657C9XC_Starlingf5.png)
Attempting to Join Starling fails with the error message "An unexpected error has occurred. You may need to refresh your page (press F5)." (4338807)
Why do I see the error "Object doesn't support property or method 'querySelector'" on F5 BIG-IP while attempting to log in?
![F5 load balancer sample configuration - Documentation for BMC TrueSight Operations Management 11.3 - BMC Documentation F5 load balancer sample configuration - Documentation for BMC TrueSight Operations Management 11.3 - BMC Documentation](https://docs.bmc.com/docs/TSOperations/113/files/892260471/935632345/1/1566706051652/image2019-8-25_9-37-30.png)